The World Wide Web (the “Web”) grows larger and larger every day. Many users of the Web access it multiple times a day every day of the week using a variety of communication devices, such as Personal computers (PC), phones, tablets, cameras and Internet Protocol Television (IP-TV) devices. Advances in mobile technologies have made it easier for a user to capture content (e.g. audio content, video content, image content), and different social network and video sharing Web sites make it possible for the user to share such content on the Web. The amount of content is growing rapidly and researchers are working on smarter ways to search, retrieve and share such content.
There are a number of commercial services that makes it possible to search, recommend and share content, such as YouTube and Facebook.
YouTube enables a content owner who uploads a content item (a video file in this case) to YouTube to specify a privacy setting for the content item. For example, the content owner can specify whether the privacy setting for the video should be set to “Public”, “Private” or “Unlisted”. A “Public” privacy setting allows anyone to watch the video. A “Private” video can only be seen by the content owner and up to fifty invited users. Making a video “Unlisted” means that only people who have the link to the video can view it and the video will not be listed on YouTube. A “Public” video, therefore, has no access control at all, a Private video relies on the server being 100% trusted, and the Unlisted videos relies on “security by obscurity” and also won't satisfy an “honest but curious” model. Similarly, Facebook allows its users to set access rights on information uploaded by the user to Facebook, but the user must rely on Facebook to correctly enforce the user's specified access rights. See e.g., Hart, M., et al., More Content—Less Control: Access Control in the Web 2.0, In Proceedings of the Web 2.0 Security & Privacy Workshop (W2SP'07) (available at www.cs.sunysb.edu/˜rob/papers/cbac-w2sp07.pdf, retrieved on Feb. 25, 2014).
What is desired is, for example, an improved method for distributing content items to authorized users.